US3006331A

US3006331A - Apparatus for dressing grinding wheels and holding work pieces thereto

Info

Publication number: US3006331A
Application number: US723538A
Authority: US
Inventors: Carl A Akert
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-03-24
Filing date: 1958-03-24
Publication date: 1961-10-31
Anticipated expiration: 1978-10-31

Description

Oct. 31, 1961 RQ n AND HOLDING A. AKERT 3,006,331 APPARATUS Fo REssING GRINDING WHEELS woRx PIECES THERETO Filed arch 24. 1958 4 Sheets-Sheet 1 Oct. 31, 1961 Y c. A. AKERT 3,006,331

APPARATUS FOR DRESSING GRINDING WHEELS AND HOLDING WORK PIECES THERETO Filed March 24, 1958 4 Sheets-Sheet 2 i@ @Maa/52W oct. 31, 1961 C. A. AKERT 3,006,331

APPARATUS FOR DRESSING GRINDING WHEELS v AND HOLDING WORK PIECES THERETO Filed March 24. 1958 4 Sheets-Sheet 3 3f/aide@ Oct. 31, 1961 3,006,331

C. A. AKERT APPARATUS FOR DRESSING GRINDING WHEELS AND HOLDING WORK PIECE-S THERETO Filed March 24. 1958 4 Sheets-Sheet 4 Wal Hmm

United States Patent Cce 3,006,331 Patented Oct. 31, 19761 3,006,331 APPARATUS FOR DRESSING GRINDING WHEELS AND HOLDING WORK PIECES THERETO Carl A. Akert, 948 Cuyler Ave., Chicago, Ill. Filed Mar. 24, 1958, Ser. No. 723,538 18 Claims. (Cl. 12S-11) This invention relates to grinding wheels; to a tool adapted to dress or prole grinding wheels with both arcuate and flat surfaces; and to a novel grinding wheel auxiliary tool which readily may be employed to accurately dress a grinding wheel without the use of indicator gauges or other measuring devices, and which during `actual grinding operations further may be arranged for accurately and assuredly positioning the work piece for which the wheel is dressed.

Devices of the general character of the type disclosed herein, of course, have been known and extensively used for some time. Further, the technique of grinding surfaces of work pieces with profiled abrasive wheels is quite advanced and rapid. However, when using these known devices initially to dress a grinding wheel to the desired shape, the preparation of the wheel is both time consuming and tedious, and more often than not consumes far more time than the actual grinding operation. Besides, almost without exception, such known devices are of complicated construction and operation -and further require the use either of extraneous separate steel yguide tapes, special templates, gauge blocks, height and indicator gauges, or other measuring means to achieve the desired wheel profile. Diiiiculty of adjustment and lack of precision in practice are common; cut and try techniques or operations prevalently are practiced to properly dress a Wheel. These practices obviously are objectionable; since, they not only require considerable time to achieve the desired results, but further require the employment of highly skilled and expensive operators. Moreover, once a grinding Wheel is dressed to the desired shape, none of these known devices provides means whereby the Work piece for which the wheel is shaped may be readily held for the actual grinding operation. Such provision, besides being of great convenience, could appreciably increase the utility of the auxiliary device and cut down total expenditure of time and preparation when grinding specially shaped surfaces.

The present invention, in contrast, contemplates the provision of a novel device with which grinding wheels may be dressed accurately and conveniently to various profiles; which provides its own means for measuring various dressing operations; and which further is adaptable to hold the Work piece, for which a wheel is specially dressed, when the same is being ground.

Accordingly, a primary object of this invention is to provide an improved auxiliary device for use with grinding Wheels, which device overcomes the foregoing and other shortcomings found in other prior art devices used for similar purposes.

Another primary object of this invention is to provide a combination tool arranged for dressing arcuate and other surfaces on grinding wheels, and for holding a Work piece for which a wheel is ground to shape.

Stated somewhat diiferently, it is an object of this invention to provide a tool for use with grinding wheels, and including an arbor for detachably receiving a Work engaging member which may be, for instance, either a grinding wheel cutting point or structure arranged to hold the Work piece for which a wheel is dressed to grind the same.

Another object is to provide means whereby the arbor and the work engaging member carried thereby may be readily and precisely positioned relative to the grinding wheel, there being provision incorporated within the herein tool for accurately measuring the positioning movement of the work engaging member.

As an aspect or corollary of the foregoing object it is within the contemplation of the present invention to provide a tool having, -within limits defined only by its own size and the size of the Wheel to be dressed, infinite adjustment and measuring means for positioning the Work engaging member. p

Another objectof this invention is to provide a tool whereby the abrasive surface of a grinding wheel may be accurately profiled without requiring highly skilled and expensive labor for such operation.

A further and more specic object is to provide a tool adapted to profile both flat and arcuate shaped surfaces on a grinding wheel, and further to incorporate in said tool novel measuring means whereby the cutting element thereof may be readily and precisely positioned to produce the desired shaped surface on said wheel.

A still further specific object of this invention is to provide a grinding wheel dressing tool which, when employed to profile arcuate surfaces, has easily adjustable stop means providing limits for conning the cutting tool within a prescribed path to achieve the desired wheel profile.

Other speciiic objects of this invention are to provide the herein tool with means whereby its arbor and work engaging member may be linearly or rotatably positioned, including means -for measuring the aforesaid movements; to incorporate the arbor as a slidable head having actuating and measuring means in the form of a calibrated micrometer adjustment to achieve linear movement; and to provide a rotary spindle to carry the slidable head, the spindle having a novel indexing plate with an annular array of stops for measuring and limiting rotary movement.

Another specific object is to provide an auxiliary tool for use with, and dressing of, a grinding wheel, the tool having a work engaging arbor or carrier including a novel plate having positionable stops for limiting rotary movement of a carrier mounted cutting tool when dressing an arcuate surface in said wheel; the plate further including an annular array of stops for measuring angular positioning movement of a carrier mounted Work piece when grinding the surface of the latter With said wheel.

Ancillary objects are to provide a grinding wheel auxiliary tool which is strong of construction, yet has simplicity of design and a relatively few number of parts, and which thus is economical to manufacture; and to provide a tool which otherwise is Well adapted to perform the services required of it.

The vforegoing and other objects, advantages and features of construction will become more apparent upon a consideration of the following description together with the accompanying drawings.

In the drawings:

FIGURE 1 is a side elevation view, partly in crosssection, showing the auxiliary device embodying the present invention prepared to dress a wheel;

FIGURE 2 is a cross-sectional plan view taken on line Z--Z in FIGURE 1;

FIGURE 3 is a plan view of the auxiliary device;

FIGURE 4 is a front elevation view of the same;

FIGURE 5 is a diagrammatic view illustrating the manner in which the tool cutting element is variously positioned to prole a convex arcuate surface of a grinding Wheel;

FIGURE 6 similarly illustrates posioning of the tool to achieve or profile a concave grinding wheel surface;

FIGURE 7 is a View taken on line 7 7 in'FIGURE 1;

FIGURE 8 is an enlarged fragmentary view showing the positionable stops;

FIGURE 9 is a front elevation view of the work engaging member employed to hold the work piece for which a Wheel is dressed;

FIGURE 10 is a fragmentary cross-sectional view taken on line 10-19 in FIGURE 9;

FIGURE 11 is a front elevation view of the housing structure in which the slidable head is mounted;

FIGURE 12 is a view partly in cross-section illustrating means whereby positioning of the rotatable plate may be interpolated between positions defined by its annular array of stops;

FIGURE 13 is a view taken on line 13-13 in FIG- URE 1; and

FIGURE 14 is a cross-sectional view taken on line 14-,14 in FIGURE 1.

The structure selected for illustration is not intended to serve as a limitation upon the scope or teachings of the invention, but is merely illustrative thereof. There may be considerable variations and adaptations of all or part of the teachings depending upon the dictates of cornmercial practice.

Referring to the drawings, the present invention for the purpose of illustration is embodied in a tool 21 intended for use with a magnetic chuck 22 of the grinding device. Support for the tool 211 is provided by a pedestal or base 23 having a ilat undersurface 24 and made of suitable magnetic material. An upstanding standard or vertical support bracket structure 25 is provided medially of the base 2,3 and integrally therewith. The support bracket structure 25 is provided with an opening 26 extending horizontally therethrough, and in which there is mounted a bearing collar 27 in bearing contact with a rotatable shaft 28. The bearing collar 27 protrudes outwardly .from the support bracket structure 25 for engagement with an annular shoulder 2.9 integrally provided in shaft 28, thereby preventing axial movement of shaft 28 to the left, as seen in FIGURE l. At its outer or rearward .end 30, shaft 28 has mounted thereto an axially extending handle 31 which is suitably knurled to facilitate handling vand turning of the shaft 28. A set screw 3-2 provides means for facile attachment and removal of the handle V31 to and from the shaft 28.

At its end 33- extending forwardly from the support structure 25, the shaft 2S carries an assembly 34 which includes a housing 35, an annular member 36 encircling housing 35 and press fitted to and secured thereon, and stops 37, 38, positionably adjustable on member 36. To facilitate mounting of the

stops

37, 38, member 36 is provided with an annular array of uniformly angularly spaced threaded openings 39, and each stop is provided with a body portion 4() having an arcuate slotted opening 41 therein for coincidental arrangement with the array ,of threaded openings 39. The effective or protruding portion 42 of each stop extends generally radially with respect to the array of openings 39. To secure each

stop

37 or 38 at a desired position, head screws 43 may -b e provided for extension through the respective slot 41 and threadable engagement into matching openings 39.

The housing, 35, as seen in elevation in FIGURES 1, 2 and 11, is provided in its front surface with a longitudinal passage 44 communicating between what normally are its upper and lower surfaces 45, 46, respectively. At its forward side 47, the passage 44 is enlarged and covered by spaced

plates

48, 49, secured to the housing 35 by suitable fasteners, such'as screws 50, to in effect provide an undercut passage in the housing 35. A head 51 is slidably lmounted in the passage 44, the head 51 being provided with guides 52 at opposed sides thereof for matching engagement with the undercut construction within the housing 35.

To slidably position head 51 a Vscrew adjustment is provided and includes a shaft 53 Iwhich is rotatably jour- Vnalled in the housing 35 and mounted therein against Vaxial movement.

through an opening in a boss 55 provided reanwardly of the head 51 and integral therewith. Turning of shaft 53, thus, correspondingly causesrhead 51 to move slidably in either of opposed directions in passage 44.

At its outer end the shaft 53 is provided With an appropriately calibrated and knurled handle 56, an indicator 57 further being provided on housing 35 to facilitate reading of the calibrations 58. On the face of plate 46 a further Vernier scale 59 may be provided lwhile the head 51 may be provided -with a form of pointer or indicator 60 by which head movement further may be measured, the combined readings of the scales 58, 59, being such as to give measurements in a manner similar to the usual micrometer. A set screw 61, extending through housing 35 and engageable with the slidable head 51, is provided to lock the head 5-1 at any desired setting.

The assembly 34 is mounted securely to the forward end 33 of the shaft 28 by means of another set screw 62 which is arranged to bear against the shaft end 33, as -best seen in FIGURE 2. The enti-re assembly 34 thus may be readily mounted to and removed from the shaft 28.

The slidable head 51 further carries a :forwardly extending carrying nlock or mounting boss 63 having a horizontal central `bore 64 and rigid vertical lip 65 at one side thereof. A set screw 66 projects radially into the bore 64, in preparation for receiving and retaining the shank of a work engaging member therein.

Referring to FIGURES l, 3 and 4, the Work engaging member is exemplified therein as a cutting tool 67, including a shank 68 matingly engagea'b-le Within the bore 64,an outwardly extending arm portion 69 integral therewith, and provided with a bore 7i) wherein there is seated the shank 71 of a mounting member 72 carrying a cutting element 73 which preferably is a diamond. A set screw 74 is threadable into the arm 69 for engagement with the shank 71 t-o retain Ithe latter in bore 79. As seen in FIGURE 3, the lip 65 is engageable against the at side surface 75 of arm 69 to prevent the latter and its shank 68 from turning in bore 64.

It will -be apparent that as shaft 28 is rotated by Vmanipulation of handle 31 the entire assembly 34 rotates.

Correspondingly, the

stops

37, 38, and in particular their protruding portions 42, follow a predetermined circular path.

Referring back to FIGURES 3 and 4, a spring biased `stop pin 76 is mounted in a sleeve 77 for axial movement therein. The sleeve 77 is fixed to the side of the support structure 25, while the pin 75 further is so arranged and positioned as to be capable of being selectively projected or interposed into the circular path of the protruding portions A42 of stops 37, 33 to limit the movement thereof, and, consequently, to limit theV rotation of the ent-ire assembly 34. To facilitate axial positioning of pin 76, at one end thereof there is provided a knurled handle 78.

Refer-ring to FIGURES l, 5 and 6, the cutting element 73Vis illustrated in readiness to dress or prole a grinding wheel '79 which generally is mounted for rotation about what may be considered a fixed axis (not shown). Further, when dressing a wheel 79 the center line of the tool or axis of rotation l of the shaft 28 is aligned generally parallel with the medial plane of the vwheel 79, or perpendicular to the grinding wheel axis of rotation. As a result as shaft 28 rotates it sweeps the cutting element 73 in an arcuate path generally perpendicular to the plane of the wheel 79. This, of course, is true when the cutting element is offset from the axis of rotation 80. When the cutting element 73 is positioned directly in alignment with the axis of rotation S0, rotation of shaft 28 merely turns the element about a pivot point coincident with the axis Si). For `the purpose of calibration land measurement, that point at which the element 73 is directly upon the axis of shaft 2S rotation is designated the zero or centered position of the Itool and the calibrated scales 58, 59, accordingly are set at a zero or starting reading.

To achieve this zero setting of cutting element 73, the arm portion 69 is provided with an offset 81 of sufficient dimension to compensate for the mounting height of the element 73 above the arm 69.

`FIGURE 5 illustrates the cutting element 73 at alternate positions, shown in phantom lines, when dressing a convex surface 82 on the grinding wheel 79. To achieve the desired radius of curvature on the wheel surface, the cutting element is first positioned below the axis of rotation 80 of shaft 2S at a distance corresponding to the desired radius of the surface 82. This is achieved by turning micrometer screw handle 56 and measuring olf the distance on calibrated scales 58, 59. To measure oi the desired amount or length of arc through which the element is to travel the limit stops 37, 38, are appropriately mounted to the correct openings 39 and pin 76 is projected int-o the path of rotation of ythe stop portions 42 -to thereby provide limits dening the ends of the arcuate path which the portions 42, and consequently the cutting element 73, travel.

Similarly, the concave surface 83 cut in the grinding wheel is Vachieved by measuring o the desired radius of curvature on the scales 58, 59. In this case, however, the cutting element is disposed or positioned above the axis 80. The sweep of the cutting element 73, or the length of its arc of travel, again is defined by appropriately setting the

stops

37, 38.

Referring to FIGURES 9 and 10, the tool is illustrated with another form of work engaging member mounted thereto. As shown this member includes a shank 63a matingly engageable in the 4bore 64 and capable of being secured therein by set -screw 66. A generally flat plate structure S4 is carried by the shank 63a and further has an undercut slot 85 provided in its forward flat surface 86. The plate 84 may be of any general shape, although it is illustrated as circular, and lfurther it is provided with threaded openings 84a extending therethrough and arranged in the herein exempliiication in a series of concentric annular arrays of openings. The work engaging member, or plate 84, is employed to hold work pieces (not shown) to be ground by the grinding wheel. The work pieces generally are strapped or bolted to the plate 84. Often, once a 'wheel 79 is dressed, using the work engaging member cutting tool 67, the tool 67 may be removed, the plate 84, with the work piece to be ground mounted thereon, set in place, and the actual grinding operation allowed to proceed. Other times the work Vpiece may require truing on the plate 84. But in either case, accurate movement of the slidable head 51 correctly positions the work piece relative to the wheel 79, and precision positioning is readily achieved by measuring the movement on the scales 58, 59.

As further seen in FIGURES 9 and l0, the plate 84 Vmay carry a V-block 87 mounted thereto. To mount the V-block 87, a passage 88 communicates between opposed surfaces of the same, and a screw 89 extends in the passage 88 to a position Whereat it is threadably engageable in a square headed nut 90 sildably mounted in the undercut slot 85. Once the V-block is positioned as desired, tightening `of the screw 89 with the nut 90 locks it in place. The slot 85 is so arranged that with the housing 51 set at the zero position and the axis of shank 68a is coincident with the axis of shaft 28, the slot 85 extends radially of the axis of shank 68a and shaft 28. The slot 85 is further arranged to extend diametrically across the plate 84.

The V-block 87 further is provided with

parallel Slots

91, 92, respectively provided in its

opposed sides

93, 94. A clamp 95 is mounted to the V-block `87, the clamp comprising an inverted U-shaped member 96 having inwardly facing

legs

97, 97, arranged for slidable mounting in the

slots

91, 92. A screw 98 is threadable through the base portion 99 of the U-shaped member 96 for engagement against a work piece 109 held on the upwardly

dverging surfaces

101, 102 of the V-block 87. As the screw 98 is threaded down into engagement with the work piece 100, the U-shaped member 96 is drawn upwardly and the work piece 100 is held firmly in place. Referring back to FIGURES 1 and 7, the member 36 is provided with means for angularly positioning the assembly 34, and in particular the plate 84 when the same is carried thereby. This means is exemplified herein by arranged as a second annular array of openings 103 in member 36 concentric with the openings 39 therein. A stop 104 is arranged on support structure 2S for selective engagement in any opening 103, the stop 104 being mounted in -a sleeve 105 for axial movement ltherein. A compression spring 106 is provided about stop 104 and is anchored between a collar 107 on stop 104 and a shoulder 108 within the sleeve 105. Medially of its ends stop 104 is provided with a diametrally extending pin 109 providing opposed projections intended -for selective registry with diametrally opposed slots 110 in sleeve 105 when the stop 104 is located in its foremost position whereat it is seated in lan opening 103. At its outermost end the stop 104 is provided with a knurled knob 111 by which it may be axially and radially moved. It will be understood that to render the stop 104 ineffective, it is withdrawn, against the action of spring 106, tol a position whereat upon radially turning the knob 111 the pin 109 is positioned to engage against the outer end of the sleeve 105. For the purpose of brevity, only the actuating structure of pin 104 has been described in detail; although, the structure for pin 76 is similarly arranged As the handle 31 is turned, it rotates the assembly 34, the plate 84 carried thereby, and the work piece mounted to the plate 84. To position the work piece with reference to the grinding Wheel 79 so as to grind surfaces thereon at any desired angle, the assembly 34 is Ilocked at the desired angular position by engaging the stop 104 in the opening 103 positioned before it. As illustrated in FIGURE 7, there are twelve openings 103 uniformly angularly spaced apart by thirty degrees. Further, appropriate marks may be provided on member 36 to yfacilitate grinding. That is, if a hexagonal shaped work piece is to be ground, the operation may be performed by .successively positioning those openings 103 having a 6 designation thereat before the stop 104. Similarly, the surfaces of three and four sided work pieces may be ground in the same manner. When it is desired to lock the assembly 34 yand Work piece at -an angular position other than those :for which the openings 103 are provided, the lock structure 112 shown in FIGURE 12 is employed. This structure 112 includes a screw 113 threadable in an opening 114 in standard 25 and engageable against shaft 28 to lock lthe same in interpolated positions intermediate those Afor which 'the openings 103 are provided.

Thus, with yan url-profiled wheel 79, that is one having only a flat grinding surface thereon, angular surfaces may be ground on a work piece by engaging the same with the wheel 79. And, this is `accomplished Without necessarily profiling angular grinding surfaces into the grinding wheel.

It further should be observed that ythe member 36, its array of openings 103, and the stop 104 selectively engageable therein, ideally provide means whereby the slidable head 51 may follow -a linear path disposed at any angle. Thus, with the cutting tool 67 mounted to head 51, and the member 36 rotated to -a desired angular position, by properly manipulating the screw adjustment handle 56, the cutting element 73 may be moved relative to and across the face of the grinding wheel 79 to proiile or dress a predetermined angular surface thereon.

In much the same manner, as explained hereinbefore, with a mounting plate 84 tixed to the head 51, yangularly positioning member 36 correspondingly angularly positions the work piece secured to plate 84. Thereafter, relative movement between the wheel 79 and work piece, to bring the latter into contact with the wheel 79, grinds the desired surface on the work piece.

To prevent backlash and inaccurate movement of the micrometer screw 54, the split friction construction shown -in FIGURES 1, 13 and 14 may be provided. As illustrated, the boss 55 is of .-a slotted construction and has -

machine screws

115, 115, provided therein to draw the `

lboss portions

117, 117, together to vary the frictional engagement with screw 54 as wear occurs. If the adjustment is too tight, it maybe changed slightly by turning screw 116, which bears against one of the portions 117,

'to ease the `frictional engagement with screw 54.

Briefly, operation and use of the herein tool is as follows. To provide an arcuate surface in a grinding wheel lthe tool is set as seen in FIGURE l.

Thereafter, the radius of curvature of Ythe desired surface is measured off by turning screw S4 and measuring off the correct distance on the calibrations 58, 59. To limit the arc or sweep of the cutting element 73, the

stop structures

37, 38, are set on member 36 and the cooperable pin 76 is moved to an e'lfective position whereat it is engageable with the stops. To provide a convex surface Vin the grinding Wheel, the cutting element 73 is moved below the axis of rotation 80; while to provide a concave surface on the wheel 79, the cutting element 73 is moved to a measured position above the axis 80. When proiiling such arcuate Surfaces lon a wheel, the sweep of the cutting element 73 is in a plane generally perpendicular to the plane of the Wheel 79.

To grind an angular surface on the wheel 79, the entire assembly is rotated -to the predetermined angle and is locked in position by engaging stop 104 in the proper opening 103 positioned before it. If the angular surface is `other than those -which the openings 103 predetermine, the assembly 34 may lbe rotated to the desired angle and locked in position by screw 113. Thereafter, by turning screw lhandle 56, `the head 51 carries the cutting element 73 angularly across the wheel 79 to provide the desired angular surface thereon. I-t will be apparent, of course, that by employing the herein structure it is possible to provide a combination of angle and radius curvatures on the :wheel 79.

When grinding a work piece, the cutting tool 67 is replaced by the appropriate work piece retention structure shown in FIGURES 9 and 10. Gener-ally, to grind small articles of round configuration the V-block structure 87 is employed. Larger work pieces, and those of varied shape, generally are strapped to plate 84 and trued Ithereon. Thereafter, the work piece is introduced to the surface of the grinding wheel 79. Specifically, angle grinding is achieved by setting member 36 at the desired langles and introducing the -work piece to the at proiled wheel 79. As another example, after a wheel is dressed, for instance with a concave profile, the plate 84 is tted to the head 51 and arranged to introduce the work piece, for which the wheel 79 had been proiiled, to the wheel 79. For this operation the work piece is moved in a direction generally parallel with the plane of the wheel 79 or perpendicular to the axis of rotation thereof.

Generally, when dressing arcuate surfaces into a wheel 79, and when employing the V-block structure S7 to grind a work piece of Vround configuration, the assembly 34 is locked in a vertical position, `as seen in FIGURES 1, 4 and 9. From such position, positioning movements of the ywork engaging lmember may be readily measured. However, it should be understood that positioning movement of the work engaging members along paths other than those achieved with the set up in FIGURES 1, 4 and 9 may be readily measured without any appreciable calculation.

The herein invention thus provides a convenient and easy to use tool both for dressing grinding wheels and holding work pieces to be ground and for which the wheels are dressed. It should be understood that when redressing a wheel 79, the amount of wheel diameter reduction can be compensated for by a corresponding Vmovement of the wheel Vtowards the cutting element.

Alternatively, the amount of reduction in diameter may be `compensated yfor by correspondingly increasing the micrometer positioning movement of the element 73, as read on the calibration 58, 59.

The herein construction further provides a tool which may be readily broken down and reassembled as the need arises. The rotatable shaft 2S, its handle 31, housing 35 and annular member 35 are arranged for quick attachment and detachment. For that matter, however, they may be of integral construction depending upon production and use considerations and the dictates of commercial practice. The assembly 34 includes the housing 35, `head 51 slidably mounted therein, and annular member 36 which as a unit combine to provide a novel Work engaging arbor or rotatable carrier further provided with its own integral measuring means for accurately positioning the work engaging member carried thereby. The member 36 further provides structural indices both for limiting the sweep of the cutting element 73 when dressing arcuate surfaces and means for angularly positioning the arbor either for dressing angular surfaces on a Wheel 79 or grinding a Work piece.

With the arrangement of the parts above described, it will be apparent that a highly simple, relatively inexpensive and very accurate grinding wheel auxiliary tool is provided. The replaceable and interchangable Work engaging members provide a substantially increased utility for a single tool of this character. These features, coupled with the fact that accurate positioning movement of the work engaging member is measured without the employment of extraneous indicator gauges and the like provide a tool of enhanced use and value heretofore unknown.

It will be understood, as indicated above, that changes in 'construction and arrangement of parts may be resorted to Without departing from the field and the spirit of the invention; that in this application only one 4form of the invention has been disclosed; and that the scope of the invention is deiined in the appended claims.

What is claimed is:

l1. A grinding wheel auxiliary tool comprising: a base, a vertical support bracket rigidly xed to said base, a carrier assembly revolubly mounted about an axial shaft carried by said base bracket, a housing and a head mounted for adjustable movement diametrically of the axis of rotation of the carrier assembly, a work engaging member detachably carried by the head, a micrometer screw drivably associated with the head to move the work engaging member relative to said shaft for measured distances in either of opposed directions from said shaft axis, and means in association with the micrometer screw calibrated to the work engaging member to indicate and directly measure linear positioning movement of the head and the work engaging member carried thereby for predetermining the arc or" movement of said work engaging member relative to a grinding wheel rotatively mounted in fixed relation thereto.

2. The grinding wheel auxiliary tool described in claim 1 and additionally including an indexing member in rigid association with the carrier assembly and provided with an annular arrayV of angularly spaced structural indices, and means arranged for selective cooperable action with any of ,the structural indices thereby to effect limitation of the angular swing of the carrier assembly and the Work engaging member carried thereby.

3. The grinding Wheel auxiliary tool described in claim 2 wherein the Work engaging member comprises an arm mountable to the head and a grinding Wheel cutting element detachably carried by the arm in axial alignment with said carrier assembly shaft.

4. The grinding Wheel auxiliary tool described in claim 3 wherein the indexing member and its structural indices -comprise a plate member provided with an annular array of uniformly angularly spaced openings concentric With the axis of rotation of the assembly and a pair of stop andassi members selectively positionable in any of the openings to predetermine the arc of rotation of the assembly, the means cooperable with the structural indices being selectively interposable into the path of the stop members and engageable thereby to limit the swing rotation of said carrier assembly.

. 5. The grinding wheel auxiliary tool described in claim 3 wherein the work engaging member comprises a support plate provided with means whereby a work piece is mountable thereto.

6. The grinding wheel auxiliary tool described in claim 5 wherein the indexing member and its structural indices comprise a plate member provided with an annular array of openings therein concentric with the axis of rotation of the assembly, and the means cooperable with the structural indices comprises a pin selectively seatable in the openings to lock the assembly and the plate carried thereby at selected predetermined angular positions.

7. The grinding wheel auxiliary tool described in claim 6 and additionally including means associated with the base and arranged to lock the assembly in angular positions other than those dened by the annular array of openings.

8. The grinding wheel auxiliary tool described in claim 6 and additionally including indexing marks on the plate member to designate those openings of the array of openings positionable before the pin so that specifically shaped work pieces may be ground.

9. The grinding wheel auxiliary tool described in claim 5 wherein the means provided with the support plate includes a work piece mounting block adjustably positionable on the support plate and having downwardly converging surfaces for seating a work piece thereon, and clamp means cooperably arranged with the block for maintaining the work piece thereon.

10. A grinding wheel auxiliary tool comprising: a frame including a ilat base adapted for seating at the work area of a grinding machine and an upstanding support extending from said base; a horizontal shaft rotatably mounted in the upstanding support; a handle provided adjacent one end of the shaft to effect manual rotation thereof; a housing xably carried at the other end of said shaft for rotation therewith; a member rigidly associated with said shaft and having an annular array of uniformly angularly spaced structural indices arranged concentric with the axis of rotation of said shaft; means arranged for cooperable action with said indices and limitation of the angular positioning of said shaft; a carrier head mounted in said housing and movable therein diametrically across said axis of rotation; a micrometer screw rotatably mounted in said housing, restrained therein against axial movement, and threadably engageable with said carrier head to move the latter relative to said shaft on said upstanding support for measured distances in either of opposed directions from said shaft axis; calibrations associated with said screw and arranged for registry with indicating means on said housing to directly measure linear positioning movement of said carrier head relative to said shaft; and a work engaging member including a shaping tool in axail alignment with said shaft detachably carried by said carrier head whereby said micrometer screw and calibrations directly predetermine the path of movement of said work engaging member relative to a grinding wheel rotatively mounted in fixed relation thereto.

1l. A grinding wheel auxiliary tool comprising: a support bracket frame, a rotatable shaft fixedly supported on said bracket frame, a handle provided for said shaft to effect manual oscillation thereof, a work engaging member, structure arranged with said shaft for rotation therewith and provided with positioning means whereby said work engaging member is movable and indexed for direct measurement relative to and diametrically across the axis of rotation of said shaft, said work engaging member including dressing instrumentalities in axial kalignment with said shaft,

means for Calibrating angular rotation and linear movement of said work engaging member including an indexing member provided rigid with said shaft and having an annular array of uniformly spaced structural indices arranged concentric with said axis, means cooperable with said indices to limit angular positioning of the shaft, and calibrations associated with said positioning means for directly measuring linear positioning movement of said work engaging member on said support bracket frame relative to said shaft to predetermine the path of movement thereof relative to a grinding wheel rotatively mounted in fixed relation thereto.

12. A grinding wheel auxiliary tool comprising: a support frame seatable at the work area of a grinding machine, a shaft rotatably mounted on said frame, means on said shaft to effect manual rotation thereof, a Work engaging member, a housing carried on said shaft for rotation therewith, a carrier lhead mounted to the housing for movement therein diametrically across the axis of rotation of said shaft and provided with means for detachably receiving the work engaging member, a micrometer screw drivably associated with said 4carrier head to move the same in either of opposed directions, calibrations associated with said screw for directly measuring linear positioning movement of said carrier head and said work engaging member relative to said shaft on said supporting frame to predetermine the radius of the arc of movement for said work engaging member, an indexing plate in rigid association with said shaft and provided with an annular array of openings therein concentric with said axis of rotation, stops adiustably positionable in said openings to predetermine the arc of rotation of said shaft, and means mounted with said frame and selectively interposable into the path of said stops for engagement therewith as said shaft is rotated to limit the degree of shaft rotation and predetermine the arc of displacement of said work engaging member, whereby said micrometer screw and indexing plate directly predetermine the path of movement of said work engaging member relative to a grinding wheel rotatively mounted in fixed relation thereto.

13. The grinding wheel auxiliary tool described in claim 12 wherein the work engaging member comprises an arm mountable to said carrier head and an element for profiling and dressing a wheel.

14. 'I'he grinding wheel auxiliary tool described in claim 13 wherein the indexing plate further is provided with a second annular array of openings which are uniformly angularly spaced and also arranged concentric with said shaft, and means mounted to said frame and selectively seatable in the openings of the second array thereof to lock said shaft, said indexing plate, and said work engaging member in predetermined angular positions.

15. The grinding wheel auxiliary tool described in claim 12 wherein the work engaging member comprises a work piece support structure provided with means whereby a work piece is mountable thereto, and additionally including a second annular array of openings in said indexing plate uniformly angularly spaced from openings adjacent thereto and also arranged concentric with said axis of rotation, and means mounted to said frame and selectively seatable in the openings of the second array thereof to lock said shaft, said support structure, and the Work piece mounted thereto in predetermined angular positions.

16. A grinding auxiliary tool comprising: a support frame, a shaft rotatably mounted on said frame, means on said shaft to effect manual rotation thereof, a work engaging member, a housing carried on said shaft for rotation therewith, a carrier head mounted to the housing for movement therein and provided with means for detachably receiving the work engaging member, a micrometer screw drivably associated with said carrier head to index and move the same in either of opposed directions relative to said shaft axis for direct measured distances therefrom, calibrations associated with said screw 1 1 for directly measuring linear movement of said carrier head and said work engaging member relative to said shaft on said support frame to predetermine the radius of the arc of movement for said work engaging member, an indexing plate in rigid association with said shaftk and provided with an annular array of openings therein concentric with the axis of rotation of said shaft, and means mounted to said frame and selectively seatable in any of said openings to lock said shaft and said work engaging member in predetermined angular limiting positions,

`whereby said micrometer screw and indexing plate directly predetermine the path of movement of said work engaging member relative to a grinding wheel rotatively mounted in fixed relation thereto.

17. The grinding wheel auxiliary tool described in claim 16 wherein the work engaging member comprises a grinding wheel dressing element provided With means for mounting the same to the head.

18. The grinding wheel auxiliary tool described in claim 16 wherein the work engaging member comprises a support plate provided with means for mounting a Work piece thereto.

References Cited in the le of this patent UNITED STATES PATENTS 893,954 Huel Iuly 21, 1908 Y1,997,862 Halborg et al. Apr. 16, 1935 2,343,637 Bochenek Mar. 7, 1944 2,404,148 Thompson July 16, 1946 2,442,453 Bley June 1, 1948 2,642,856 Calloway June 23, 1953 2,744,515 Bruderick May 8, 1956 FOREIGN PATENTS 334,558 Great Britain Sept. 5, 1930 517,883 Italy Mar. 3, 1955 720,317 Great Britain Dec. '15, 1954 OTHER REFERENCES Wheel Dressing, etc., by Yarema; Machinery, pages 20 469 to 471, March 13, 1952, vol. `80. (Copy in Division